Apparatus for drilling holes.



G. H. GILMAN.

APPARATUS FoR DRILLING HOLES.

APPLICATION FILED MAR. 4. |908.

Patented Dec. 11, 1917.

I n v e nolm GQ90129612 Gallmann by M' "z Tap sTATTs PATENT sonaron.

GEORGE H. GILMAN, 0F CLAREMONT, NEW HAMPSHIRE, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO SULLIVAN `MACHINERY COMPANY, OF BOSTON, MASSACHUSETTS, A.

CORPORATION 0F MASSACHUSETTS.

APPARATUS Fon DBI'LLING HOLES.

Application filed March 4, 1908. Serial No. 419,129.

To aZZ whom t may concern:

Be it known that I, GEORGE I-I. GILMAN, a citizen of the United States, residing at Claremont, in the county of Sullivan and State of New Hampshire, have invented an Improvement in Apparatus for Drilling Holes, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to apparatus for drilling holes, more particularly, though not necessarily exclusively, for quarrying or mining purposes.

In rock drilling it is lthe present practice to mount the drilling implement vor tool adjacent the rock to be drilled, and as the hole deepens to feed the tool toward the rockfor a limited distance. The drilling implement may be either a reciprocating drill with its cutter reciprocatively attached to the driving element, or an impact or hammer, drill with its cutter adapted to rest against the stone while struck a succession of hammer blows. The feed of the tool toward the rock, however, is limited by the length of the cutter shank, and, when the tool has been fed in close approximation to ythe mouth of the hole, the cutter must be with- ,drawnv and replaced by another having a longer shankto cut the hole deeper. In cutting deep holes cutters of excessively long shanks'and of great weight and mass must be employed. If a reciprocatory drill is used, cutters of great length require tools of correspondingly greater power to lift them out of the cut. If an impact tool is used, the blows are delivered at an increasingly greater distance from the cutting edge and through an increasingly greater mass of steel. so that the effectiveness of the blows steadily diminish as the hole deepens.

My present invention contemplates the introduction of the cutting tool itself together with the cutter into and within the drilled hole, the tool with the cutter being fed or advanced within the hole as the latter deepens, thereby malringit Vpossible to actuate thecutter through the piston or other driven element of the tool in close and effective proximity to the working edges of the 'tool'. This avoids the necessity of constantly changing cutters as the hole deepens to pro- '.rrde'- cutters ci ,increasing -.1en.gth, thereby Specification of Letters Patent.

' drill.

Patented Dee. 11,1917.

securing greater cutting efliciency which comes from. the use of ashorter length of cutter, as well f assecuring other important advantages.

My invention will bev best understood by reference to the following description when taken in connectionwith the accompanying illustration of one specific embodiment thereof, while, its scope will be more par- 1 ticularly pointed out in the appended claim.

In the drawings Figure l shows one application of myinvention in a simplified aspect, to a drill tool of the pneumatic hammer type.

Fig. 2 is amodication ofthe application i yof the invention shown inFig. 1, showing the employment of special guiding means for the tool.

Fig. 3 illustrates the preferred form of my invention, showing they employment of feeding means and the application of the invention to the drilling of horizontal or lateral holes; and

`Fig. 4 lis a detail showing the arrangement of exhaust passages in the hammer Referring Vto the drawings and to the embodiment of my invention there shown in Fig. 1, the drill tool l is shown provided L with the cutter v2, both introduced bodily within the drilledhole 3, and having no exteriorv attachment other 'than the flexible pipe 4L which is adapted to supply working pressure fluid from any suitable source (not shown) to the tool. y

Any suitable form of drill may be employed either of the reciprocatory drill tvpe or the impact hammer type, but in the illustrated embodiment of `my inventionI have shown a tool of the pneumatic impact hammer type. The detailed construction of the tool is of no particular consequence', as bearing on the broad principles of my invention,

the construction of the tool shown, however,

being substantially the same, except as to external form and the arrangement of the exhaust passages, as that shown in my prior U. S. lPatent No. 853,921, dated 4May '14,

This tool is providedy with a piston-hammer or impact member 5 adapted to strike the head or upper end of the .cuttershank 6, the'piston being reciprocated under the of compressed air or "other motive pressure fluid admitted through tbe flexible or other supply pipe, the latter preferably having an axial or central attachment to the 'upper end of theV tool. Pressure iiuid enters the tool through the supply passage S in the plug or cap piece 9 threaded into the tool cylinder 1 and passes to the valve block 10 where its admission to and exhaust from the cylinder is controlled by a suitably con- 10 structed distributing valve, such, for ex# ample, as is shown in my aforesaid prior patent.

While the tool may have any desired shape orvform, preferably give the samea barrel or cylinder-like formation of substantially uniform circular cross-section, so `that it will not only be compact in size but will tend to guide and aline itself by Contact with'the sides of the drilled hole. The effective cutting diameter of the cutter should, however, preferably be greater than the greatest outside diameter of the tool, or, at any rate, of that portion of the tool which is intended to enter the drilled hole, so that the tool will offer no obstruction in its advance. The cutter maybe as much wider than the tool as may be desired, although f preferably, land particularly where no separate or additional guiding and alining means is employed, the cutter is slightly wider than the tool, as represented in Fig. y1, so that while the chippings and dust `will have la reasonably free exit passage between the sides of the tool and the sides ofthe hole, the tool itself will be self-alining, or kassist the alinement as the hole deepens.` Y

Any suitable or desired means for clearing the bottom of the hole of chippings anddirt, either through the use of water or exhaust pressure Huid, or both, may be employed, but. in the illustrated form of the invention I use the exhaust, the latter being emitted from the rear of the tool, so that it is directed toward the mouth of the hole. This produces a vacuum tending tov draw the chippings out and discharge them at the 'mouth of the hole. To provide for this discharge of the exhaust, the exhaust openingsll from th'e'valve block communicates with the annular space 12 between the block and the cylinder walls,`and with the rearwardly directed exhaust passages 13 formed inthe walls of the plug or cap'piece 9. In addition to the rearward discharge of the'v exhaust, a portion of the exhaust, or, 'if desired, the entire exhaust (the .passages `15 being entirely or partly closed) may be discharged forwardly through the cutter bit, Athe latter having,for that purpose, an V`axial passage extending the entire length ofithe -shanlrto the cutter edge (see Fig. 1');

Iny drillinga lhole withtheV device shown in-Fig l, the latter may be provided-with a cutteror bit ofany. desired length of shank, ebutas shawn inthe drawingsyits vlen'gth'they be reduced to a minimum, so that the effective blow of the hammer piston at Yall times is' delivered in close and unchanging proximationV to the cutting edge ofthe tool and vthe greatest cutting "eiiiciency' at all 70 times maintained at the end of the out, as well asV at the commencement thereof, no matter how deep the hole.

In the form of the invention shown'in Fig. 1, in starting the hole the tool may be held by hand or in any suitable guiding device, but as soonas" the hole has deepened enough to receive the tool, or a portion thereof, theweight of. the tool may be relied upon to hold the cutter in the bottomv of the cut, and the contact between the barrel-like cylinder and the walls' of the hole may be relied upon-t0 guide thetool and keep the hole straight as the cut deepens. The motive iiuid supplied to the toolmay be 'controlled 85 in any suitable manner andthe operation of the toolstarted or `stopped at will, as may be desired, as byfmeans of the :throttle valve 14 located in a'sectionvof the hose. If desired, the hose may be the sole external 'connection'withthe ltool and aloneV may be utilized to introduce thetool into thefhole or withdraw the same when the cut =is fin ished,` or at other times,suchfas lwhenit is desired to sharpen the cutterl bits.

Automatic rotating devices of'any well f known or usual'type may vbe employed for the cutter, although, as shown, the cutter and tool will'tend to'exec'ute a rotative or semi-rotative movement sufli'cientlto `shift 100 the cutter about its axis between -successivef blows, thereby producing the desired rotative effect.

lVhile in'Fig.-`l l have shown thei tool as provided withlno independent toolguid-ing 105 devices, suitable tool guidingmeans, Vif dev sired,'may be employed. For example, in Fig. Q, I have shown substantially the vsame formof to'o'l 1,-there being provided, however, betweenk the iiexible hose '4: and the tool 110 a preferably rigid pipe or other connection 12 15 through which'the motive iiuid may be conveyed. This rigid rod or tubularv attachment l15, projectin'gfrom the mouth of the hole,-may be employedmanually to guide or direct the tool "as its cutting advances; 'or fixed guiding devices, such'as the plug piece 16 lixedly heldf in 'themouth-fof the hole, may be utilizedlfor this purpose, the 'piece having y'afsliding and guided `engagement 120 within lthe plug. The plug piece 16 is shown aperturedat 17 to 'permit the escape ofthe exhaust and the fchippings.'

The application lof my linvention is not confined or restricted'to the drillingof ver- 125 tical or other downwardly 'directed holes, but may beutilized to drill holes at anyv desircd direction eitherV horizontal, inclined or upwardly ,directed For; example, the to'ol may-.lbs manualyfforcedito follow the cutter. 13u

, pressure.

into the hole by using an attachment, such as a seat formed in the split encircling anchor 40 the rigid attachment shown in Fig. 2, or automatic pressure fluid or other feeding devices may be employed to hold the tool to the work and cause the tool with its attachment automatically to enter or advance within the hole.

In Fig. 3 I have shown a cutting tool 1 and cutter 2 similar to that shown in Fig. 2, and an attached rigid tubular supply connection 15, all cooperating to drill a horizontal hole. There are here provided, however, coperating fluid pressure cylinder and piston feeding elements for the automatic advance of the tool, the piston 18 being connected to the tool rod 15 and adapted to slide within the cylinder 19, the latter held rigidly fixed at the mouth of the hole. Pressure fluid beingv admitted through the flexible connection l under the control of the throttle valve 14 to the outer end of the feeding cylinder, the feeding piston 1S with its attached tubular rod and tool, is forced forward into the drilled hole under the full supplied working At the same time, the pressure duid admitted to the feeding cylinder passes through an axial passage in the piston 18 and through the tubular rod 15 to supply the tool, causing the simultaneous operation thereof. The feeding cylinder may be held up toward the mouth of the hole to receive the backward thrust of the tool by any suitable means. In the illustrated form, the forward end of the cylinder is provided with an elongated bearing part 20 with which the rod 15 has sliding engagement, the outer portion of the part 20 being tapered at 21 and threaded at 22. The tapered portion may be drawn tightly by the lock nut 23 into 24:, the latter being firmly anchored into the sides of the hole by means of the points 25 My invention is not limited to the employment of any particular form of motive fluid or driving power, nor is the same limited t0 the employment alone of an impact drill member as distinct from a reciprocatory drill. Where a. reciprocatory drill is employed, however, preferably some means should be provided apart from the mere rest of the cutter upon the bottom of the hole for holding the tool in fixed relation to the bottom thereof.

My invention is not limited to the particular form of apparatus herein shown or to the precise steps described in carrying it into effect, but is susceptible of various applications and Vembodiments quite different and remote from those herein described, but which are comprehended within the scope of the claim.

Claim:

v In a device for drilling rock, the combination with a fluid operated drill tool, of a cutter having an edge of greater width than the outside dimension of said tool, means for discharging a portion of the exhaust fluid in a rearward direction from the rear end of said tool, and means for discharging another portion thereof through the cutter at or adjacent the cutting edge thereof. Y

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE H. GILMAN. Witnesses J. A. BRUCE, E. J. BRUCHARD.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

